boost flutter at wot along with sputtering

I'm thinking your TPS might be flaking out like others have said. Do you have a graphing meter that you can read the TPS WAVEFORM? It could look fine on a DVOM but it wont pick up a glitch easily. Do you have another tps you could put on there and test?

Also I dont think dielectric grease is conductive, BUT if you packed the hell out of the connectors it may have pushed a pin out a little (highly doubtful but worth a shot anyways).

How old is your PCV valve? That could be letting boost into the crankcase and throwing things off. I would look at the simple $hit, and make sure everything is 100%.

If this post seems redundant I'm sorry, but just trying to help a brother out ;)
 
TurboBuRick said:
I really don't think so. Looks more to me like spark or fuel is going away. What plugs are you running?
Click to expand...
the spark is showing on the powerlogger in the advanced and fuel is staying full at wot is lowers as the boost goes down. i am running new ngk ur 5's

DailyDrifter said:
I'm thinking your TPS might be flaking out like others have said. Do you have a graphing meter that you can read the TPS WAVEFORM? It could look fine on a DVOM but it wont pick up a glitch easily. Do you have another tps you could put on there and test?

Also I dont think dielectric grease is conductive, BUT if you packed the hell out of the connectors it may have pushed a pin out a little (highly doubtful but worth a shot anyways).

How old is your PCV valve? That could be letting boost into the crankcase and throwing things off. I would look at the simple $hit, and make sure everything is 100%.

If this post seems redundant I'm sorry, but just trying to help a brother out ;)
Click to expand...
thanks for the help. tps is perfect showing on the powerrlogger no glitches and th epcv is new along with a check valve in line with it. the car when it hits full boost it sputters and bogs untill i let off the gas a little then it pulls hard till the boost hits full again
 
The logger has no way of showing spark drop out, what you see is commanded spark advance not actual spark.

Try some A/C r42ts plugs. Gap them at a tight .030. At this point you have nothing to loose. Plugs are cheap and easy to change.

Spark, air or fuel. One of them is going south. It's pretty cut and dry. If fuel is there and air is getting in and out then there is only one other thing left. ;)

I want to see you nail this down.
 
TurboBuRick said:
The logger has no way of showing spark drop out, what you see is commanded spark advance not actual spark.

Try some A/C r42ts plugs. Gap them at a tight .030. At this point you have nothing to loose. Plugs are cheap and easy to change.

Spark, air or fuel. One of them is going south. It's pretty cut and dry. If fuel is there and air is getting in and out then there is only one other thing left. ;)

I want to see you nail this down.
Click to expand...

thanks its either too much fuel or not enough spark. when i turn off alky and lower timing to 20/18 and lower boost too just slipping on wastegate or leaving it off it still falls on its face at wot
 
well i took it on the highway and eased into it slooowly all the way to the floor and it pulled clean all the way thru. then i did a wot punch and it sputters and noses over vut if i lift a little and ease into it it pulls hard and clean. what is this
 
I'd trace-out/ check all positive (+) battery leads/ wires & routings, as it seems one may be grounding-out with a WOT torque-surge engine movement--that may not occur during a gradual run-up...

If you have not yet tried another battery & alternator--I'd do that too...
 
TurboMonte 2 said:
I'd trace-out/ check all positive (+) battery leads/ wires & routings, as it seems one may be grounding-out with a WOT torque-surge engine movement--that may not occur during a gradual run-up...

If you have not yet tried another battery & alternator--I'd do that too...
Click to expand...

all cables are good no burn or grounding marks. battery and alternator check out excellent. got 14.1 at battery and alternator and showing 13.8 on scanmaster. nothing showing that something is grounding out on scanmaster when car noses over
 
OK, my next shot in the dark... Get a piece of wire and the correct Packard(?) pin for the MAF sensor connector. Temporarily remove the original ground pin from the MAF connector and install the new pin with the new wire. Run that wire to a new dedicated ground, effectively bypassing the original ground for the MAF sensor in the factory wiring harness. See if that works...

I had to do this in a local car last year...


K.
 
NCTURBOS said:
OK, my next shot in the dark... Get a piece of wire and the correct Packard(?) pin for the MAF sensor connector. Temporarily remove the original ground pin from the MAF connector and install the new pin with the new wire. Run that wire to a new dedicated ground, effectively bypassing the original ground for the MAF sensor in the factory wiring harness. See if that works...

I had to do this in a local car last year...


K.
Click to expand...

This may help with the MAF dropouts. This is why I asked him if he had a clean pull logged. All the PL files are junk from mashing the gas pedal.
 
i think the maf drop outs are from the air bieng pushed back thru the maf pipe. this happens when the boost flutters.
 
QUIP'6' said:
i think the maf drop outs are from the air bieng pushed back thru the maf pipe. this happens when the boost flutters.
Click to expand...

I think you would see the LV8's drop out as well if that was the case... Like before, when chips didn't have the 255 lock-out feature?

Razor said:
Or maybe the drop outs are cuasing the boost flutter :eek:
Click to expand...

My thoughts as well...


K.
 
Razor said:
Or maybe the drop outs are cuasing the boost flutter :eek:
Click to expand...
very true

NCTURBOS said:
I think you would see the LV8's drop out as well if that was the case... Like before, when chips didn't have the 255 lock-out feature?



My thoughts as well...


K.
Click to expand...
also very true.

one thing i did see is someone on the board had there cam going bad and was having the same symptoms. when he eased into it it pulled clean but when he stomped on it it would flutter. wonder if i stomp onit it ramps up fast and dumps 65 psi of fuel plus alky and the valves arent opening enough to burn it but if you go slow it consumes it at a better rate.


GOING RIGHT NOW TO MAKE A RUN. BE BACK SOON
 
Well went out and did 3 runs none of them layed over. even from a dead stop. it did sputter only in 1st to 2nd then cleaned out and sputttered very slightly from a kickdown from 3rd to 2nd. the first and third run are easing into gas from a roll the second is a dead stop run. I AM CONFUSED!!!!. is it also normal for the wastegate solonoid to drop percentage every gear and did have a maf drop out on one run. this is with 10 perdent fuel out of all gears. 23/21
 

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